University of Illinois Urbana-Champaign

Effect of loading sequence on cumulative fatigue damage of 7075 T6 aluminum alloy

Spitzer, Robert; Corten, H.T.

Permalink

https://hdl.handle.net/2142/111905

Description

Title
Effect of loading sequence on cumulative fatigue damage of 7075 T6 aluminum alloy
Author(s)
  • Spitzer, Robert
  • Corten, H.T.
Issue Date
1961-06
Keyword(s)
  • Loading Sequence
  • Fatigue Damage
  • Aluminum
Abstract
For conditions of fluctuating stress amplitude consisting of repeated block of cycles of two stress amplitudes and continuously varying amplitudes, it has been shown that the mean fatigue life may be predicted using the linear summation of cycle ratios hypothesis and a “modified σ-N relation.” This approach assumes that the initial sequence of high, intermediate and low stresses does not significantly influence the fatigue life since, in general, the number of cycles in each repeated block is small compared to the life of the member. Recent studies by Naumann and Hardrath suggest however, that the sequence of applying high, intermediate and low stresses in repeated block experiments may change the fatigue life by a factor of from 2 to 4. This investigation was undertaken to clarify this question. It was found that changing the sequence from high followed by low stresses to low followed by high stresses in each repeated block did not change the life by more than the length on one repeated block of cycles, or by a factor of from 1.07 to 1.14.
Publisher
Department of Theoretical and Applied Mechanics. College of Engineering. University of Illinois at Urbana-Champaign
Series/Report Name or Number
  • TAM R 193
  • 1967-0489
ISSN
0073-5264
Type of Resource
text
Language
eng
Permalink
http://hdl.handle.net/2142/111905
Copyright and License Information
Copyright 1961 Board of Trustees of the University of Illinois

Owning Collections

Technical Reports - Theoretical and Applied Mechanics (TAM) PRIMARY
TAM technical reports include manuscripts intended for publication, theses judged to have general interest, notes prepared for short courses, symposia compiled from outstanding undergraduate projects, and reports prepared for research-sponsoring agencies.